Shoe-filling composition.



OTTO EISENSCHIML, OF CHICAGO, ILLINOIS, .ASSIGNOR,, BY MESNE ASSIGNMENTS, TO NEW PROCESS FILLER CO., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SHOE-FILLING COMPOSITION.

No Drawing.

the under side of the insole in order to prepare a level foundation for the outer sole. a number of different compounds have been developed for this purpose, the manner of applying these compounds being substantially as follows:

The compound, after first being heated to -a temperature considerably higher than maximum ordinary atmospheric temperatures, istaken up in small quantities by the operator, by means of a spoon or spatula, and placed in the cavity, the mass being afterward, while still warm and plastic, squeezed level into the interstices of the shoe cavity by means of considerable pressure exerted through a heated roll or other device.

However, so far as I am aware, afiller which is absolutely satisfactory in every respect has heretofore not been produced. Some of these filler compounds are 'not completely plastic when heated to a working.

temperature, or cannot be spread evenly with a knife, for this reason excessive pressure must be employed in order to squeeze the material evenly into all parts of the cavity, which necessitates the provision of more or less complicated machinery for applying the compound to the shoe. Some of these compounds have a very disagreeable, penetrating odor, which frequently becomes quite pronounced when the shoe 1s worn 1n hot weather, or in any place where the shoes may happen to be stored or kept.

Other fillers are not suificiently sticky when applied and do not adhere properly to the leather on either side of the filler, which seriously aflects the wearing quality of the shoe, in that this defect frequently causes the filler to bunch up, roll, or travel under the movement of the foot and cause the formation of high spots on the sole which results in undue wear at these points.

The essential features of a shoe-filling Specification of Letters Patent.

Application filed June 16, 1915. Serial No. 34,416.

compound are, first, cohesiveness; second, adheslveness; and third, a proper melting po nt. The composition must be sufliciently adhesive to stick to the surfaces of the inner and outer soles; it must have the proper amount of coherency so that it will not disintegrate, crack or crumble, while at the same time, its melting point must be higher than the maximum atmospheric temperature, and, on the other hand, low enough .to prevent damage to the leather during its appllcatlon to the shoe. In the efiort to obtain all of these desirable features, the binder has heretofore been composed of a number of different substances or ingredients of widely different physical and chemical properties; for instance, such substances as dextrin, wax tailings, rosin, and lubricatlng oil have been used in the same compound. Naturally, such a composition is qulte expensive to manufacture and is in the nature of a compromise. In such a compound, the ingredients are not chemically combined with each other, but are simply mixed together mechanically, the mixture thus having no inherent chemical stability whatever.

A shoe-filler compound should be absolutely waterproof at all times so that if Water, by any chance, does'leak through the outer sole, it will be arrested by the filler and prevented from penetrating to the interior of the shoe. However, it has been found that in attempting to make fillers which will answer all other requirements, the waterproofing qualities of the compound have been considerably sacrificed. Some of these compositions, although waterproof when applied to the shoe and for a short time afterward, gradually lose their waterproofing qualities. Many fillers are tempered with oil in order to reduce the melting point, and this oil, in most cases, gradually separates out of the compound in to crack and disintegrate. The hardening of the compound, with the resulting inflexibility of the sole, often ruins the shoe in a comparatively short time, this hardening.

4 effect belng particularly pronounced where fects or disadvantages in use, and which will siderably possess other meritorious qualifications, as will hereinafter appear.

At the present time the tendency is to make shoes as light as possible, consistent with proper wearing qualities. The wearer insists that a modern shoe should be of extremely light weight and yet have as long or a longer life than the old-fashioned heavy-weight-shoe; and to this end, I select as the body of my improved filler a material which has a very low specific gravity. An excellent material for this purpose is cork, which, besides having a low specific gravity, possesses a high degree of resiliency, which it retains practically indefinitely.

The body material for which, as stated, I prefer cork, is comminuted by shredding finely or by granulating' into particles conlarger than the grains of ordinary coarse white sugar. It is then ready for incorporating with the binder; that is, the material which is used to bind the individual particles of the filler-body together into a coherent mass, and at the same time impart to the compound the necessary waterproof and other properties.

After discarding a vast number of different materials, as a result of numerous experiments extending over a long period of time, I have discovered that prepared asphaltum possesses all of the physical and chemical properties which are required in a perfect binder. The term asphaltum, as loosely employed, includes a large number of mineral compounds which, although mainly hydro-carbon in character and having substantially the same chemical composition, possess widely differing physical properties. This is especially true of the melting point, which varies greatly, depending upon the degree of refinement and the process employed in preparing the asphaltum for the market. Although the chemical composition of the various asphaltic compounds varies slightly, I have found that many asphaltums are suitable for my purpose, provided that they have a melting point of approximately 120 F., which is high enough to prevent the compound from liquefying or becoming fluid at ordinary atmospheric temperatures, while at thev same time it is unnecessary to heat the compound to a dangerous or excessive temperature when applying the filler to the shoe. The melting point of the asphaltum is not sharply defined, the fusing of the mass being gradually efi'ected as the temperature is raised from 110 F. to 130 F.

No particular skill or special apparatus is required for mixing together the binder and the body material. In practice, 1 heat the asphaltum under a slow fire in a caldron or kettle. After the mixture has attained the required degree of uniformity and fluidity, the cork is added and thoroughly stirred and mixed, the mixture being meanwhile maintained at a suflicient temperature to prevent solidifying of the binder. Enoughbody material is added to the liquid binder to thoroughly coat the particles and cause them to adhere together and prevent the presence of voids in the finishedfiller compound. I find that this requires about one part of comminuted body material, by Weight, to three parts, by weight, of the asphaltic binder. Such a combination results in the formation of a substantially homogeneous mass, practically fi'ee voids, while at the same time it has the right degree of plasticity when heated to a working temperature.

One of the particular benefits or advantages derived'from the use of my compoundfor filling shoes is due to the fact that no particular skill or special machinery or apparatus is necessary in order to apply the compound to the shoe. This is due to the fact that asphalt, when heated to the fusing point, does not become instantly fluid but remains in a semi-plastic condition, with a somewhat buttery consistency, over a comparatively wide range of temperature around the fusing point. -While in this condition, it does not stick to hot metal, and thus the compound can be spread in-the shoe cavity with the same ease as butter upon bread. After having heated the compound to a temperature of approximately 160 F., the workman, bymeans of a spoon or dipper, places in the shoe cavity the required quantity" of heated filler compound, and

afterward, by means of a hot spatula or spreader knife, is enabled to evenly and uniformly spread the compound in the cavity. The free working qualities of the material when hot are such that only a comparatively slight amount of pressure on the knife or spatula is required in order to' force the compound into the corners or interstices of the shoe cavity. Thus I obviate the necessity of supplying expensive and cumbersome steam-heated rolls or other apparatus for applying pressure to the filler compound after it is applied to the shoe, apparatus may be used wherever already installed.

After the shoes have been filled, it is although such unnecessary to store them in a drying room or to let them stand for any considerable length of time, since the mixture sets practically instantaneously, or, at any rate, as soon as the temperature reaches that of the ordinary atmosphere. I thus save the expense of providing sufiicient space to store the shoes while the filler body is curing or setting, and I also save the loss due to the delay in the cycle of manufacturing operations.

After numerous practical experiments which I have conducted with my improved filler, I find the compound is very flexible under all conditions, it does not age or lose its resiliency in course of time, and it will not check, crack, or disintegrate after years of service in a shoe. It is absolutely unaffected by atmospheric conditions, retaining its original elastic and waterproof properties in hot, cold, wet, or dry climates.

It has been found in many cases that the soles of shoes which were filled with all of the filler compounds which have so far been brought to my attention were completely spoiled if the shoes were allowed to remain at a high temperature for a considerable time; for instance, if placed on the top of a steam radiator and allowed to remain there over night. This latter practice, by the way, although a most reprehensible one, is not so uncommon as might be imagined. The reason that such heating spoiled the shoes was because of the fact that in those old filler compounds, the application of considerable heat for a sustained period causes the binder of the filler compound to split up or separate out into its various ingredients, the binders, as heretofore stated, not'being homogeneous chemical substances, but merely-mechanical mixtures of such ineon gruous materials as dextrin, rosin and oil. The result was that the oil oozed out and the filler was ruined. The great advantage of asphaltum in this respect is, first, the fact that it is a homogeneous chemical unit, and,

second, that its viscosity, even at high tem-' peratures, is very high so that it does not easily penetrate the pores of leather or other small crevices. Long continued tests by heating shoes filled with my improved compound to a sustained temperature of 150 F. indicate that no separation Whatever takes place between the cork and the asphaltum binder, which is a single, homogeneous, chemical compound and contains no ingredi ent which might have a tendency to separate out or be absorbed by the leather.

My improved filler'has a natural adhesiveness which makes it stick tightly to the inner and the outer sole, and prevents the compound from balling up, rolling, or traveling in bunches under the action of walking while the shoe is warm. The layer of filler thus retains its original thickness in the &

cavity between the inner and the outer soles and causes the shoe to retain its shape, and consequently lengthens its life considerably. There is no oozing of the binder through the leather or the seams or interstices of the shoe, and a shoe filled with compound is absolutely free from objectionable smell or odor, owing to the fact that the binder does not contain volatile ingredients which dry out or evaporate from the binder after the shoe is produced.

The compound is absolutely waterproof under all conditions and after years of service, the waterproof quality of the shoe being greatly enhanced by the natural adhesiveness of the compound, which causes it to stick tightly to the sides of the cavity and prevents gaps or channels which would admit moisture to the interior of the shoe. The compound is particularly resilient or flexible and retains its pliability indefinitely, so that a shoe filled with my improved compound is originally very fiexible and comfortable to wear and does not stifi'en up in course of time.

In the course of my experiments I have discovered that asphaltum difl'ers widely from the substances which have heretofore been usedin shoe filler compounds, in that it is possible to add to the asphaltum quite a considerable percentage of certain oils, for instance, a fairly heavy mineral lubricating oil, without sacrificing the inherent chemical stability of the material, which has previously been referred to. This feature is of .asphaltum has a somewhat higher melting point than is required. The chemical aflinity between the asphaltum and the oil which is I added thereto for tempermg, is so great and the asphaltum is of such viscosity, that even Where the quantity of oil added to the binder is as high as ten or fifteen per cent, there is absolutely no tendency for the oil to separate out from the compound even if the latter be heated to a high temperature for a long period of time.

One of the most important advantages of my invention is due to the relative cheapness of the asphalt compound, which can be purchased in the open market for a very -few cents per pound. This enables me to manufacture my shoe-filler vastly cheaper than many of the old compounds containing a long list of comparatively expensive ingredients which must be prepared or compounded at high cost by skilled labor. In addition to the cheapness of my compound, which costs much less per pound than the shoe-filler compounds which have heretofore been brought to my notice, I have found that it will fill more shoes of a standard size than will the old materials; for instance,

one pound of any of the standard filler com'- 130 pounds heretofore in use will fill approximately forty pairs of shoes, whereas my material will run about fifty pairs to the pound.

Although I have described what I consider to be a preferred embodiment of my invention, it should be understood that the details of the composition may be varied somewhat without departing from the spirit of the invention, which I do not wish to limit, except as specified in the appended claims.

I claim 1. A shoe-filler compound, composed of a body of comminuted cork and a binder of mineral asphaltum having a melting point 15 of approximately 120 F.

2. A shoe-filler compound having the following composition: one part, by weight, of comminuted cork, and three parts, by weight of a mineral asphaltum having a 20 melting point of approximately 120 F.

OTTO EISENSCHIMIJ- Witnesses:

C. A. Scans, EMILIE Rosa. 

